IA is a common, rapidly progressive, highly morbid, and frequently fatal infection in immunocompromised patients, especially in patients with chemotherapy-induced neutropenia or who are immunosuppressed as a result of receiving glucocorticoid treatment for graft-versus-host disease (GVHD). Timely diagnosis with prompt initiation of appropriate antifungal therapy improves clinical outcomes. Unfortunately, clinical and radiographic manifestations are nonspecific, and standard culture and antigen diagnostic approaches lack sensitivity and specificity for IA. Definitive diagnosis still relies on biopsy, which is often unacceptably morbid and frequently uninformative in these debilitated patients.